The present invention relates to a new form of bio-available iron which is even safely intravenously administrable
Iron deficient anemia is ubiquitous. It is one of the truly universal afflictions. Since the late 19th century iron preparations have been available, and oral ferrous sulfate is still a safe, cheap and effective means of replenishing iron stores in the vast majority of anemic patients. However, it does have considerable disadvantages associated with its use, e.g., side effects of nausea, vomiting, constipation, etc. These are due, at least in part, to the relatively large daily doses required for adequate absorption and hemoglobin response.
Moreover, ferrous sulfate cannot be administered intravenously. In fact, there is presently no satisfactory, intravenously administrable iron supplement. Yet, in certain cases it is impossible to give oral iron preparations. For example, patients who can take nothing by mouth and receive total parenteral nutrition (TPN) frequently require transfusion therapy merely to replenish diminished iron. Premature and sick infants often require extended periods of TPN which exacerbates the normal physiologic anemia of the newborn. TPN is conventionally effected by intravenous administration of commercially available TPN solutions. Although containing most essential vitamins, minerals and amino acids, currently available TPN solutions do not contain iron since there is no acceptable intravenous form.
Other situations also exist in which one must forego the oral route of iron administration. These involve certain patients with iron deficient anemia associated with pregnancy or chronic renal failure and patients unable to take oral iron for any reason.
Such patients often receive painful intramuscular (IM) injections of an iron dextran complex to satisfy their iron supplement requirements. (See, e.g., U.S. Pat. No. Re. 27,240.) All the patients mentioned above would greatly benefit from a safe form of intravenous (IV) iron.
Various forms of iron have been suggested for intravenous administration, e.g., Fe bound to polymeric substrates, or chelated by various ligands, saccharates, dextrans, etc. (See, e.g., U.S. Pat. Nos. 3,886,267, 3,367,834, 4,058,621, 3,275,514 and 3,686,397.) However, all have been unsuccessful and/or possess such adverse side effects that practical utilization has not occurred. The only commercially available intravenous iron preparation is iron dextran (Imferon .sup.R). However, IV administration of this compound is accompanied by an unacceptable incidence of anaphylaxis, which has severely limited its use (Physicians' Desk Reference, p. 1201 (1979)).